Bob discusses some of the disadvatages against sealing EIFS at ground levels
EIFS was originally developed as a retrofit cladding material for solid substrates like concrete and masonry. EIFS was intended for use on vertical exterior walls, but over the years its use has migrated to all sorts of wall-like applications, some of which work quite well while others simply do not. One of the common marginal uses of EIFS is near or below the ground. This month's column will give you some food for thought for the next time someone wants to use EIFS near or below grade.
First, remember that EIFS is not a waterproofing material, but that it is water shedding. This is why it should not be used for roofs or on large flat surfaces. If it is used on roof-like surfaces, it can absorb water, which in turn can work its ways through the EIFS and start deteriorating the substrate. There's no way to make EIFS totally waterproof; it simply is not glass or metal. But in its use as a vertical cladding, it is plenty waterproof enough to keep the wall dry. (If this logic appears a bit convoluted, consider why shingles are not used on flat roofs, even though they shed water when used as intended on vertical surfaces.) However, it is possible to improve the water penetration resistance of an EIFS by using special basecoat adhesives and surface sealers. These can be quite useful at window sills and on the top edges of foam shapes.